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V907 Sco Switched to the Eclipsing Mode Again
Zasche, Petr; Barlow, Brad N.; Mašek, Martin +1 more
V907 Scorpii is a unique triple system in which the inner binary component has been reported to have switched on and off eclipses several times in modern history. In spite of its peculiarity, observational data on this system are surprisingly scarce. Here we make use of the recent Transiting Exoplanet Survey Satellite observations, as well as our …
Young Stellar Object Candidates in IC 417
Rebull, L. M.; Hall, G.; Anderson, R. L. +12 more
IC 417 is in the Galactic plane, and likely part of the Aur OB2 association; it is ~2 kpc away. Stock 8 is one of the densest cluster constituents; off of it to the east, there is a "nebulous stream" (NS) that is dramatic in the infrared (IR). We have assembled a list of literature-identified young stellar objects (YSOs), new candidate YSOs from t…
The Cycles of Alpha Centauri: Double Dipping of AB
Ayres, Thomas
In mid-2023, the Sunlike dwarfs of nearby α Centauri (HD 128620 ("A"): G2 V; HD 128621 ("B"): K1 V; hereafter "AB") coincidentally both entered coronal (T ≈ 1-3 MK) low states in their long-term X-ray cycles, as captured by the Chandra Observatory and its High Resolution Camera (HRC-I). The assessment benefited from a sensitivity degradation model…
Spectroscopic Orbits of Subsystems in Multiple Stars. IX
Tokovinin, Andrei
New spectroscopic orbits of inner subsystems in 14 hierarchies are determined from long-term monitoring with the optical echelle spectrometer, CHIRON. Their main components are nearby solar-type stars belonging to nine triple systems (HIP 3645, 14307, 36165, 79980, 103735, 103814, 104440, 105879, 109443) and five quadruples of 2 + 2 hierarchy (HIP…
Radio-optical Reference Catalog, Version 1
Secrest, Nathan J.; Makarov, Valeri V.; Johnson, Megan C.
The fundamental celestial reference frame (CRF) is based on two catalogs of astrometric positions: the third realization of the International Celestial Reference Frame (ICRF3), and the much larger Gaia CRF, built from the third data release (DR3). The objects in common between these two catalogs are mostly distant AGNs and quasars that are both su…
Photometry of the Four Anti-Galactocentric Old Open Clusters: Czernik 30, Berkeley 34, Berkeley 75, and Berkeley 76
Lee, Joon Hyeop; Kyeong, Jaemann; Kim, Sang Chul +2 more
We present a BVI photometric study of four old open clusters (OCs) in the the Milky Way, Czernik 30, Berkeley 34, Berkeley 75, and Berkeley 76 using the observation data obtained with the Small and Moderate Aperture Research Telescope System 1.0 m telescope at the Cerro Tololo Inter-American Observatory, Chile. These four OCs are located at the an…
Kepler Bonus: Light Curves of Kepler Background Sources
Hedges, Christina; Martínez-Palomera, Jorge; Dotson, Jessie
NASA's Kepler primary mission observed about 116 deg2 in the sky for 3.5 consecutive years to discover Earth-like exoplanets. This mission recorded pixel cutouts, known as target pixel files (TPFs), of over 200,000 targets that were selected to maximize the scientific yield. The Kepler pipeline performed aperture photometry for these pr…
X-Ray Emission of Ultraviolet Variable Active Galactic Nucleus Candidates
Wasleske, Erik J.; Baldassare, Vivienne F.
We analyze the X-ray properties of a sample of 23 high-probability active galactic nucleus (AGN) candidates with ultraviolet variability identified in Wasleske et al. Using data from the Chandra X-ray Observatory and XMM-Newton Observatory, we that find 11/23 nuclei are X-ray detected. We use spectral energy distribution modeling to compute star f…
Evolved Eclipsing Binaries and the Age of the Open Cluster NGC 752
Pilachowski, Catherine A.; Deliyannis, Constantine P.; Shetrone, Matthew D. +8 more
We present analyses of improved photometric and spectroscopic observations for two detached eclipsing binaries at the turnoff of the open cluster NGC 752: the 1.01 days binary DS And and the 15.53 days BD +37 410. For DS And, we find M 1 = 1.692 ± 0.004 ± 0.010M ⊙, R 1 = 2.185 ± 0.004 ± 0.008R ⊙, M …
First Detection of Radio Emission Associated with a Classical Cepheid
Rupen, M. P.; Evans, N. R.; Matthews, L. D.
We report the detection of 15 GHz radio continuum emission associated with the classical Cepheid variable star δ Cephei (δ Cep) based on observations with the Karl G. Jansky Very Large Array. Our results constitute the first probable detection of radio continuum emission from a classical Cepheid. We observed the star at pulsation phase ϕ ≈ 0.43 (c…